You make too much sense sir. Bravo haha :bow
But da colors. EDIT: I still want them. Colors, while limited in the spectrum, are expanded further by mixing colors, and adding tints and hues. There are thousands, and taking a semester in Art Design, I can get specific with color names ;) 
And I would be the one to worry about the difficulty to remember if mentioned specifically. 

Anyways, so just so I completely understand, he would sense things in a 360 radius. Magic would create white "light", whereas the absence of magic would simply be darkness. Distance imposes a haze, walls impose a barrier, and the aura/light of a human/soul would be distinguished by something akin to an instinctual feeling, or maybe a different presence accompanying the light itself?